Re: devfs vs. udev

Ian Kent
2003-10-14T13:44:29Z

On Tue, 7 Oct 2003, Måns Rullgård wrote:

> Andreas Jellinghaus <aj@dungeon.inka.de> writes:
>
> >> I noticed this in the help text for devfs in 2.6.0-test6:
> >>
> >> Note that devfs has been obsoleted by udev,
> >
> > devfs works fine, lists all devices, and obsoletes makedev.
>
> That's my experience.
>
> > udev needs patching for several issues, current sysfs only exports
> > many but by far not all devices, and because of that makedev
> > is still needed to create an initial /dev.
> >
> > in short: devfs works fine. udev has quite a way to go.
> > so marking devfs obsolete was done too soon by far. but
>
> Exactly my point.
>
> I'd also like an explanation of the rationale behind the switch.
> devfs works and is stable. Why replace it with an incomplete fragile
> userspace solution? I recall reading something about the original
> author not updating devfs recently, but I can't see why that requires
> rewriting it from scratch.

Sorry to interrupt.

I have had a look at the code and looked around a bit and I'm left with
two questions.

1) What are the problems with devfs. I can't seem to find anything
specific?

2) I believe udev does not support for an increased number of anonymous
devices for such things as NFS and autofs mounts. I can't see anything in
the kernel (2.6) to improve this either. Can devfs provide improvements
for this without to much pain?

--

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